Intensity of sunlight at given position is defined as power received per unit area
so here we can say

area on which photons are received is given as

now we can find the power received due to sunlight



now we can say this power is due to photons that strikes on surface of earth
so here we can say

given here that





so it will strike 2.47 * 10^18 photons on given area per second
Answer:
The average speed for the entire run is 12 km/h.
Explanation:
The average speed is given by the following equation:

Where:
: is the total distance
: is the total time
If during the first hour, they ran a total of 13 kilometers and then, they ran 5.0 kilometers during the next half an hour we have:


Hence, the average speed is:

Therefore, the average speed for the entire run is 12 km/h.
I hope it helps you!
To find out the weight of the object, you'll need to slide the weight poises until the pointer is at zero again. Start with the two heavier weight poises and then use the lightest one to do the fine tuning. Our triple beam balance and the Ohaus triple beam balance are accurate to 0.1 grams.
-- Top picture:
'a' and 'b' have the same magnitude, and both are positively charged.
-- Bottom picture:
The charge on the particle is negative.