Question 27999
1) If the car goes from standstill to 54 mph in 5 seconds, you can find the acceleration, assuming it's uniform of course, by dividing the speed (54 mph) by the time (5 secs).
But you must work in similar units, so convert the speed of 54 mph to mps (miles per second) before you divide by the 5 seconds.

54 miles/hour divided by 3600 seconds/hour = 0.015 miles per second.

Now divide 0.015 miles/sec by 5 secs = 0.003 miles/second squared.

This means that the car is increasing its speed at the rate of 0.003 miles for each second of travel.

2) The speed of light,{{{C = 3X10^8}}} 
Distance to sun,{{{d = 149X10^9}}}

Time of travel, t = distance/speed.

{{{t = (149X10^9)/(3X10^8)}}}
{{{t = (149/3)X10^1}}}
{{{t = 497}}}seconds. Divide this by 60 to get minutes.
t = 8.28 minutes.