C. grades in courses because it depends on how much the students study to get their grades
If you wish to<u> mentally estimate</u> the <u>total cost</u> of items, <u>rounding </u>off the items to the<u> nearest half dollar</u>, then you have to consider all five items separately.
Five items cost $1.85, $.98, $3.49, $9.78, and $6.18.
1. $1.85≈$2;
2. $0.98≈$1;
3. $3.49≈$3.50;
4. $9.78≈$10;
5. $6.18≈$6.
Then the total cost is
$2 + $1 + $3.50 + $10 + $6 =$22.50.
Answer: correct choice is C
A-10......C-he didn't notice that a domino has number that will equal 49 in multiplication but will not add up to be if its less than 4 dominos
