You would use the A=Pe^rt equation here. A (total amount)= P (initial amount) e^r(rate)x t(time). Here is the equation for you to plug into your calculator. A=350e^0.45x10. The answer is..31505.99596
283 rounded to the nearest ten is 280
When rounding to the nearest ten look at the number to the right of the place you are rounding. In this case it is the 3. If the number is 5 or higher you go up to the nearest ten. If the number is lower than 5 like it is in this number you round down to the nearest ten.
The answer of this question is 284