The guy ran at a speed of 8.07783 MPH
Here's how I got my answer:
1 km/hr. = 0.621371
So, if you do
you will get your answer: 8.07783 MPH
One factor of 12 is 2. The other factors of 12 are 3, 4, and 6.
It's not perfectly clear, but you seem to be saying that each week, the
pond becomes 3% deeper than it was THE PREVIOUS WEEK.
If I'm reading that correctly, then the pond is 10-ft deep when the rainy
season begins, and after 'x' weeks later, the depth is
D = 10 (1.03)^x feet.
After 8 weeks, the depth is D = 10 (1.03)⁸ = 12.67 feet .
rounded to the nearest foot, D = 13 ft.