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No expanded working has been attached for this question yet. The verified answer is Option D.

No expanded working has been attached for this question yet. The verified answer is Option C.

Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Mosquito larvae are usually filter-feeders. They have fan-like mouth brushes that sweep water at their mouths from in front of them. In this method they filter out small particles of decaying material and microorganisms, which they then eat. While adult mosquitoes are one of many species of fluid-feeding insect.

Commensalism is a type of population interaction in which one species is benefited and another is neither harmed nor benefit. In this, epiphyte is benefited as it receives support from the tree and the tree is neither harmed nor benefited.

Social insects work together to find food and other resources and to communicate their findings to others in the community. They are capable of providing defense to their home and resources when under attack. Social insects also can displace other insects, and even larger animals, for territory and food. -Social insects are the ants, bees, wasps, and termites that have organized societies. -Butterflies are mostly solitary creatures, though some species migrate in massive numbers. -Wolves are very social animals. They live and hunt together in groups called packs. A wolf pack is really just another name for a family of wolves

From the constraint y < 3 and y > 0, the possible values for y are 1 and 2 When y = 1, 3y + 5x \(\leq\) 15 3 + 5x \(\leq\) 15 ⇒ 5x \(\leq\) 12 ⇒ 2.4 since x must be an integer greater than 0 but less than or equal to 2.4, the possible values of x are 1 and 2 When y = 2, 3y + 5x \(\leq\) 15 ⇒ 6 + 5x \(\leq\) 15 ⇒ 6 \(\leq\) 15 - 6 = 11 ⇒ x = 2.2 Again, Since x must be an integer greater than 0 and less than or equal to 2.2, the only possible integer value of x is 1 So, the pairs (x, y) that satisfy all the conditions are ( 1, 1), (1, 2) and (2, 1).

\(\begin{vmatrix}-1 & -1 & -1\\3 & 1 & -1\\1 & 2 & 1\end{vmatrix}\) = -\(\begin{vmatrix}1 & -1 \\2 & 1\end{vmatrix}\) + \(\begin{vmatrix}3 & -1\\1 & 1\end{vmatrix}\) - \(\begin{vmatrix}3 & 1\\1 & 2\end{vmatrix}\) = -( 1 + 2) + (3 + 1) - ( 6 - 1) = -3 + 4 - 5 = 4 - 8 = -4.

K = \(\begin{pmatrix}2 & 1\\3 & 4\end{pmatrix}\) K\(^2\) = K = \(\begin{pmatrix}2 & 1\\3 & 4\end{pmatrix}\) x K = \(\begin{pmatrix}2 & 1\\3 & 4\end{pmatrix}\) = \(\begin{pmatrix}7 & 6\\18 & 19\end{pmatrix}\) I = \(\begin{pmatrix}1 & 0\\0 & 1\end{pmatrix}\) K\(^2\) + K + I = \(\begin{pmatrix}7 & 6\\18 & 19\end{pmatrix}\) + \(\begin{pmatrix}2 & 1\\3 & 4\end{pmatrix}\) + \(\begin{pmatrix}1 & 0\\0 & 1\end{pmatrix}\) = \(\begin{pmatrix}10 & 7\\21 & 24\end{pmatrix}\)

If P = \(\begin{pmatrix}3 & -2 & 4\\5 & 0 & 6\\7 & 5 & -1\end{pmatrix}\) Then -2P = -2 x \(\begin{pmatrix}3 & -2 & 4\\5 & 0 & 6\\7 & 5 & -1\end{pmatrix}\) = \(\begin{pmatrix}-6 & 4 & -8\\-10 & 0 & -12\\-14 & -10 & 2\end{pmatrix}\)

a = N 100.00, d = N 20.00, Un = N 5800.00, n = ? Un = \(\frac{n}{2}\)(2a + (n - 1)d) 5800 = \(\frac{n}{2}\)( 2 x 100 + ( 20n - 20) 11600 = 200n + 20n\(^2\) - 20n 20n\(^2\) + 180n - 11600 = 0 divide through by 20 n\(^2\) + 9n - 580 = 0 solve using the quadratic formula n = 20 0r - 29 n = 20 years Years cannot be calculated in - Ve

Length of arc = \(\frac{Ø}{360} \times 2\pi\) 5.5 = \(\frac{360 - 210}{360}\) x 2 x \(\frac{22}{7}\) \(\frac{ 5.5 \times 360\times7}{150\times2\times22}\) = 2.1 length of major arc = \(\frac{210}{360}\) x 2 x \(\frac{22}{7}\) x 2.1 7.7m ≈ 8m

a(i) Diagram of the mammalian heart (a)(ii) Pulmonary circulation in mammals takes the following process: The heart muscles contract, allowing de-oxygenated blood from the right ventricle to pass through the pulmonary valve into the pulmonary artery to the lung capillaries for exchange of oxygen and carbon dioxide. Oxygenated blood from the lungs then return by the pulmonary vein to the left auricle. (b) The processes by which mammalian body reduces its temperature are: (i) relaxation of hair erector muscles (ii) increased sweat production (iii) vasodilation (iv) reduction in heat generated by muscles (v) reduction of metabolic activities by the body (vi) conversion of energy into ATP instead of heat (vii) panting/yawning also reduces temperatures.

Social insects work together to find food and other resources and to communicate their findings to others in the community. They are capable of providing defense to their home and resources when under attack. Social insects also can displace other insects, and even larger animals, for territory and food. -Social insects are the ants, bees, wasps, and termites that have organized societies. -Butterflies are mostly solitary creatures, though some species migrate in massive numbers. -Wolves are very social animals. They live and hunt together in groups called packs. A wolf pack is really just another name for a family of wolves

(a)(i) Diagram of human sperm cell (ii) Sperm cell are produced in the testis(es) seminiferous, tubules and stored temporarily in the epididymis. (b) The structure of the sperm cell enables it to function effectively in fertilization in the following ways: (i) Acrosome: This is located at the anterior end of the head which contains lytic enzymes (agents) used to dissolve the egg membrane. it enhances the penetration of the egg during fertilization. (ii) Middle piece: it contains numerous mitochondria which generate the energy used by the sperm cell to swim towards the egg. (iii) Long whip-like tail or flagellum: This is found at the posterior end of the sperm cell. It propels or moves the sperm cell. (iv)The Nucleus: The nucleus in found the head of the sperm cell contains genetic material which fuses with the nucleus of the egg/ovum. (c) Advantages of sexual reproduction are: (i) It permits variability of individuals, i.e., new varieties are produced. (ii) It enhances survival in new or changing environment. (iii) It allows for the production of hybrids for some desirable traits. (iv) It provides the means for the maintenance of chromosome number from generation to generation. (v) It enhances speciation or formation of new species and allows for the continuity of the species.

(a) Activities of man that pollute water bodies are: (1) dumping of household refuse or organic wastes into water bodies (ii) oil spillage from drilling or tankers (iii) thermal pollution, hot water from industrial plants and atomic reactors (iv) dumping of agro chemicals, e.g. fertilizers, pesticides, fungicides etc (v) dumping of dye from textile factories into water (vi) pouring detergents from homes and factories into water bodies (vii) pouring tannins from leather factories into water bodies (viii) radiations or radioactive fall-outs from nuclear plants washed into water bodies (ix) untreated sewage dumped into water bodies (x) use of dynamites/explosives for fishing (xi) use of chemicals (Gamalin/DDT) in fishing. (b) Measures for preventing pollution of water bodies are: (1)Treatment of raw sewage before discharging into water and prohibition of disposal of human waste into water bodies (2)Refuse must be burnt or buried and must not be deposited into water bodies (3)Recycling of industrial waste before discharging them into water. (4) Wastes should be discharged in controlled amounts. (5) Cooling of water from industrial plants before discharging (6) Proper sewage treatment (7) Using biodegradable detergents in controlled amounts (8) Limiting the use of pesticides and fertilizers (9) Spraying oil with detergents to spread it or cover oil with chalk powder to cause it to sink and speed up bacteria decomposition/efficient method of preventing oil spillage (10) Proper education of farmers on correct usage of fertilizers to limit run-off into water bodies (11) Enactment/enforcement of laws to prevent the use of explosives and chemicals in fishing. The methods of purifying water are: boiling, addition of chemicals, e.g. alum, and chlorination; filtering; distillation; sedimentation and boiling; sterilization, e.g. by using u. v. light