How do I accurately enter values in Mastering Physics for kinematics problems?

[madah12]

Homework Statement

http://img137.imageshack.us/img137/8650/masteringphysics.png

Homework Equations

The Attempt at a Solution

by the second derivative a = 30t-3
a(4.7)=138
do I enter as 14 * 10 or 1.4*10^2 I don't want to lose anymore marks because I don't know how to enter it
also average accelaration is 67.5 i enter it as 68?

Never mind I got it write (1.4*10^2 ,68)but I lost .3% of the grade :(((

 

[JDoolin]

Oh no! Now you won't get above 99.7%

 

[madah12]

actually the home work only cover 10% of the total grade and since we cover 10 sub section every section covers 10% of the 10% of the total grade
so I lost .3%of 10% of 10% of the total grade so I only can take up to 99.997 ! what if someone takes 99.998 lol ( to mods I wasn't spaming I was just practicing percentage problem :) )