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From the diagram, PQRS is a rectangle Area of shaded part = 72sq.cm But 72 = 3h - 4 + 6h - 4 + 4h = 72 - 16h - 8 = 16h - 72 + 8 =16h = 80 h = \(\frac{80}{16}\) = 5cm

T = W but W = W\(_1\) + W\(_2\) = (m\(_1\) + m\(_2\))g

A transformer that increases the voltage from primary to secondary (more secondary winding turns than primary winding turns) is called a step-up transformer.

The photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material. The frequency of the incident light on the substance determines the kinetic energy of the emitted electrons. The number of electrons emitted and the intensity of light incident are proportional to each other.

The fundamental frequency (Fo) = 40Hz First overtone f1 = 2 \(\times\) 40 = 80 Second overtone f2 = 3 \(\times\) 40 = 120 Third overtone f3 = 4 \(\times\) 40 = 160. Hence there are just two overtones between 40Hz and 150Hz

Bond polarity and ionic character increase with an increasing difference in electronegativity. The electronegativity (χ) of an element is the relative ability of an atom to attract electrons to itself in a chemical compound and increases diagonally from the lower left of the periodic table to the upper right.

The iodine liberation process is significantly affected by the amount of acid, that of potassium iodide added, the waiting time for the liberation, and light; therefore, the process plays a key role for the accuracy of the titration results. For a 10\(^0\) rise in temperature, time of reaction is halved i.e as temperature increases from 25 - 35, time of reaction is halved from 72 to 36. However, recall that rate of reaction = \(\frac{1}{time of reaction}\) ⇒ They are inversely proportional. Which means for a 10\(^0\) rise in temperature, if time of reaction is halved, then rate of reaction will be doubled.

2415 = 2 x 52 + 4 x 5 + 1 x 5 + 1 x 5o 50 + 20 + 1 = 7110 Convert 7110 to base 8 \(\begin{array}{c|c} 8 & 71 \\ 8 & 8 R 7\\8 & 1 R 0\\8 & 0 R 1\end{array}\) = 1078

The least length is \(\frac{40}{48}\) = \(\frac{5}{8}\) for the rod to be cut in exactly equal trips Ratio \(\frac{5}{6}\) : \(\frac{48}{40}\) \(\frac{\frac{5}{6}}{\frac{40}{48}}\) = 1 \(\frac{5}{6}\) x \(\frac{48}{40}\) = \(\frac{240}{240}\) = 1 The least length = 240cm

1m = 1.1 yard, length(L)= 50m = (50 x 1.1)yards = 55 yards Area(A) = length(L) y width (W) 1815 = 55y width (W) width (w) = \(\frac{1815}{55}\) = 33 yards But 33 yards = 30 meters

\(\frac{0.021741 \times 1.2047}{0.023789}\) = \(\frac{0.022 \times 1.2}{0.024}\) (to 216) = \(\frac{0.0264}{0.024}\) = 1.1

Let the distance from P to Q = d km (We don't need the actual value of d — it will cancel out.) Time taken from P to Q = \(\frac{\text{d}}{90}\) hours Time taken from Q to P = \(\frac{\text{d}}{45}\) hours Total distance travelled = d + d = 2d km Total time taken = \(\frac{\text{d}}{90}\) + \(\frac{\text{d}}{45}\) = \(\frac{\text{d}}{90}\) + \(\frac{2d}{90}\) = \(\frac{3d}{90}\) = \(\frac{\text{d}}{30}\) hours Average speed = \(\frac{\text{total distance}}{\text{total time}}\) = 2d \div (\(\frac{\text{d}}{30}\)) = 2d \times (\(\frac{30}{\text{d}}\)) = 60 km/h

Let the length of the square be \( L \). The area of the square is: \(A_s = L^2\) After modifications, the new length \( L_r \) and width \( W_r \) of the rectangle are: \(L_r = 1.2L, \quad W_r = 0.8L\) The area of the rectangle \( A_r \) is: \(A_r = L_r \times W_r = (1.2L)(0.8L) = 0.96L^2\) The ratio of the areas is: \(\text{Ratio} = \frac{A_r}{A_s} = \frac{0.96L^2}{L^2} = 0.96\) Thus, the ratio of the area of the rectangle to the area of the square is \( 0.96 \). Or \(\frac{96}{100}\) = 24:25

Total amount invested by A and B = N5,000 farm yield was sold for N15,000.00 profit = 15,000.00 - 5,000.00 = N10,000.00 Profit was shared in ratio 2 : 3 2 + 3 = 5 A received \(\frac{2}{5}\) of profit = \(\frac{2}{5}\) x 10,000 = N4,000.00 A receive \(\frac{3}{5}\) of profit = \(\frac{3}{5}\) x 10,000 = N6,000.00 Difference in profit received = N6,0000 - N4,000.00 = N2,000.00

I = \(\frac{PRT}{100}\) 100(A - P) = prt P = \(\frac{100A}{100 + RT}\) = \(\frac{100 \times 7000}{100 + (4 \times 3)}\) p = \(\frac{700,000}{112}\) = N6,250.00