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2.04 x 3.7 = 204 x 37 ----- 7548 = 7.548 = 7.55(2dp)

Let assume the cost price is 100% Marked up price + cost price = 20 + 100 = 120% Discount at 20% = 20/100 × 120 % of cost price Selling price = cost price − gain = (120 − 24)% of cost price = 96% of cost price Loss = (100− 96)% of cost price = 4% of cost price ∴ He will wake 4% loss

5÷ (2 − √3) Using conjugate surds [5 ÷ (2 − √3)]×(2 + √3) ÷ (2 + √3)] [5(2+√3)÷((2− √3))2] [5(2 +√3) ÷ (2)2− (√3)2] [5(2 +√3) ÷(4− 3)] = 5(2 + √3)

The trinomial = \( a^2 − 4a + 4 \\ a^2 − b^2− 4a + 4 = (a^2 − 4a + 4) − b^2 \\ (a^2 − 2a − 2a + 4) − b^2 \\ a(a − 2)− 2(a − 2)] − b^2 \\ (a − 2)2 − b^2 \\ (a − 2 + b)(a − 2 − b )\)

tan x = \(\frac{2}{3}\)(given), is illustrated in a right-angled \(\Delta\) thus m2 = 22 + 32 = 4 + 9 = 13 m = \(\sqrt{13}\) Hence, 2sin x = 2 x \(\frac{2}{m}\) 2 x\(\frac{2}{\sqrt{13}}\) = \(\frac{4}{\sqrt{13}}\) = \(\frac{4}{\sqrt{13}} = \frac{\sqrt{13}}{\sqrt{13}}\) = \(\frac{4\sqrt{13}}{13}\)

Using the general gas laws: \(\frac{P_1V_1}{T_1} = \frac{P_2V_2}{T_2}\) P\(_1\) = 800mmHg, V\(_1\) = 76cm\(^3\), T\(_1\) = 273 + 27 = 300k P\(_2\) = 760mmHg, V\(_2\) = ? T\(_2\) = 273 + 0 = 273 (@ STP) \(\frac{800 \times 76}{300} = \frac{760 \times V_2}{273}\) V\(_2 = \frac{800 \times 76 \times 273}{300 \times 760}\) = 72.8cm\(^3\) Therefore, the volume of gas at S.T.P = 72.8 cm\(^3\)

Boyle‘s law stats that the volume of a given mass of a gas, at a constant temperature is inversely proportional to us pressure. Mathematically V ∝ l/p, v = k/p (where k is constant) K = VP Let k = k1 Then, if k = k, V and P = V1P1 V1P1 = V2P2

Ray – a beam of light or radiation

XL = WL = 2πFL (w = 2πf) XL = reactance inductor (S.I unit Ω) L = inductance (L) in Henry XL = 1Ω, f = 50/π, L = ? 1 = 2× π × 50/π × L 1 = 100L i.e. 100L = 1 L = 1/100 0.01H ∴ Inductance (L) of a inductor = 0.01H

Stroboscope is a scientific instrument used to make a wave appears stationary when used

In an inelastic collision, linear momentum is conserved and energy is decreased Momentum and kinetic energy are conserved in elastic collision

Note:The principle of floatation states that a floating body displaces its own weight of the fluid or which its float. For object to sink weight of the object (W) > upthrust of the fluid (v) i.e. w > u (i.e. weight of the body (or object) mass of the fluid)

Formula for general gas law V × 1/T × P N [(PV) ÷ T] = K is constant

The appearance of pool of water on road surfaces is called MIRAGE His observation show that light from the sun ray refracted through a layer of hot air(layer) which is closed to the ground, passes from a hot air layer to the cold layer

Sun are self luminous source Moon is a non – luminous