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(a) (b)(i) E: Viable seed F: Oxygen/viable seed G: Moisture/water (ii) All the conditions of water, oxygen/air, warmth/suitable temperature, viable seed necessary for germination were present; - it is the control experiment. (c)

(a) Classification: (i) Phylum L: Arthropoda M: Arthropoda (ii) Class: L:insecta: M: insecta, (b)i) Observable Features of Members of the Class of Specimen L:-Three body divisions: head, thorax, abdomen;-Three pairs of jointed walking legs;-Presence of wings;-A pair of jointed antennae -Spiracles present;- A pair of compound eyes; -Exoskeleton of chitin/chitinous exoskeleton. (ii) Other classes of phylum of specimen L:-Crustacea-Chilopoda-Diplopoda-Arachnida. (c) Economic Importance of Specimen: (i) L: -Vector/transmits diseases; -Buzzing noise disturbs(sleep)-Causes discomfort through its bites. M: -Has aesthetic value/used as ornament, Pollinates flowers: -Destroys(citrus) fruits by feeding on them; (ii) Ways by which Specimen L/Mosquito can be Controlled -Sleeping under nets ( to prevent adult mosquito bites); Clearing the bushes around the house ( to eliminate places where mosquitoes hide and breed); -Removing all stagnant water bodies around the house ( to prevent mosquitoes from breeding); -Using/spraying insecticides in the rooms/around the house (to kill adult mosquitos) -Pouring oil on stagnant water bodies (to suffocate the larvae),-Introducing fish/bacteria, e.g. Bacillus species into water bodies (to eat up mosquito larvae and pupae); -Using mosquito repellents(to prevent adult mosquitos from biting); -Using light to attract and kill adult mosquitoes/use of mosquito trap: -Using genetically modified mosquitoes to result in early death of larvae/eggs that do not hatch. (d)(i) Observable differences between specimens L and M (ii)Similarities between specimens L and M: Both have -three body divisions/head, thorax and abdomen-proboscis; -wings: Six legs/three pairs of legs:- one pair of compound eyes; - one pair of antennae - Exoskeleton of chitin chitinous exoskeleton; - Segmented abdomens - three thoracic segments. (c) Habitat of specimens L and M: L: Houses/land/swamp/marshy areas/ dark places/tall grasses/ pond(s) M: Garden/on trees/leaves/flowers/rock surfaces/bare ground/grassland

2x = 3x - 50 alternate angle 50\(^o\) = 3x - 2x 50\(^o\) = x < NPQ = (3x - 50)\(^o\) = 3(50)\(^o\) - 50 = 150 - 50 = 100\(^o\)

< O\(Q\)P = 48\(^o\) (base angles of isoceles \(\triangle\)) m = 48\(^o\) + 48\(^o\) = 96\(^o\) (exterior angle of a \(\triangle\))

x + y + m + z = 180º but m = \(\frac{1}{2}\)(x + y + z) 2m = ( x + y + z ) Thus ( x + y + z) + m = 180º (2m) + m = 180º 3m = 180º m = \(\frac{180º}{3}\) = 60º

m + n + 90\(^o\) + 180\(^o\) (sum of angle in a \(\triangle\)) m + n = 180\(^o\) - 90\(^o\) m + n =90\(^o\)

75.0785 -35.624 -------------- 40.4545 +9.83 ------------- 50.28 to 2d.p

\(\frac{1}{3}\)(5 - 3x) < \(\frac{2}{5}\)(3 - 7x) 5(5 - 3x) < 6(3 - 7x) 25 - 15x < 18 - 42x - 15x + 42x < 18 - 25 \(\frac{27x}{27}\) < \(\frac{-7}{27}\) x < \(\frac{-7}{27}\)

The point of intersection are (2.0, 9.0) and (-1.5, 2.0)

If x = -2.5 y = 8.5

x→y means "if x is true, then y is true." The contrapositive of x→y is \simy → \simx, which is logically equivalent to the original implication.

GIVEN DATA: where \DeltaL is the increase in length = 0.01 L1 is the initial length = 100 T1 = 20 T2 = ? \alpha is the linear expansivity of iron = 1.2 x 10\(^{-5}\)^\circC Formula \DeltaL = L1\alpha\DeltaT \DeltaT = \(\frac{\DeltaL}{L1\alpha}\) \DeltaT is the change in temperature = T2 - T1 T2 = \(\frac{\DeltaL}{L1\alpha}\) + T1 T2 = \(\frac{0.01}{100 \times 1.2 x 10^{-5}}\) + 20 T2 = 8.3 + 20 T2 = 28.3

A single pulley is a device composed of a wheel on an axle over which a rope, cord, or similar implement is looped.

The cup containing water at 45∘C loses heat to the room since temperature of the room is lower than its temperature, hence its temperature reduces gradually, the cup containing water at 5∘C gains heat from the room since its temperature is lower than that of the room. hence, its temperature increases gradually, the lines are curved because as the temperature of the water changes the temperature difference between the water and surroundings also changes

In a step down transformer, there are more turns in the primary coil than in the secondary coil and more current flows in the secondary circuit than in the primary.