Answer: Raju travels at a higher speed.
Step-by-step explanation:

Speed inversely proportional to time.
As time taken to cover a particular distance decreases the speed will increase.
Raju covers a certain distance in 1 hour.
Sham covers the same distance in 2 hours.
1< 2
Thus Raju travels at a higher speed.
I have no idea.... Try to ask your teacher or your parents
Answer:
1.5 seconds
Step-by-step explanation:
h=-16t² – 16t+ 60
When the rock enter the water, the height is 0. ... h=0
0 = -16t² – 16t+ 60 = -4 * (4t² - 4t +15) = -4* (2t - 3) (2t +5)
2t-3=0 or 2t+5 = 0
t = 3/2 or t = -5/2 (time can't be negative)
t = 3/2 or 1.5
28/20 in simplest form is: 7/5
70/50 in simplest form is 5/7
Because,
28/20 divided by 2 is 14/10, divided by 2 again is: 7/5
70/50 divided by 2 is 25/35, divided by 2 again is: 5/7