Ms. sim traveled to 42 countries in 60 days. at this rate, how many countries would he travel to in 40 days?

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25

Ineed the solution to this problem and the steps.