Answer:
635 years old
Explanation:
The light reaching the earth from the sun will travel at a speed called the speed of light, and this has a universal value of 3 × 10⁸ m/s. Bearing this in mind, let us calculate the age of the light reaching the Earth from the sun:
Distance of star from Earth = 6.1 × 10⁸m
Speed of light = 3 × 10⁸ m/s
We have distance and speed, let us calculate the time of travel of the light from the star to the earth.
Distance = speed × time
6.1 × 10⁸ = 3 × 10⁸ × time

In order to do the division above, we will divide the whole numbers normally, then we will apply the law of indices to the power that says:
Xᵃ ÷ Xᵇ = X⁽ᵃ⁻ᵇ⁾

Next, we are told that there are 3.2 × 10⁷ seconds in a year.
∴ The number of years travelled by the light from the star:

please note that:
2.03 × 10¹⁰ = 20300000000
3.2 × 10⁷ = 32000000

The closest answer in the option is 635 years, and we are short of this by some points due probably to approximations in the calculation.
A continually rotating magnetic field would continuously induce current, the induced current would show alternating direction
Answer:
3. 560W
Explanation:
First we calculate the work required for the 700N weigh student to climb up by 8 meters. Work is force times distance
W = Fs = 700 * 8 = 5600J
The average power is defined as the rate of energy expended over a unit of time. In order words, work divided by time duration
P = W/t = 5600 / 10 = 560 W
B)is pills everything to the surface of the earth not sure about A