I assume that you mean 3 times 5 feet means how many feet and inches
so the answer is 5 feet and <u>blank </u> inches
or 12 inch in 1 feet so 12 times 5=60 so 60 inches
or you may have forgotton to put a number before the first inch word like 5 feet <u>3</u> inch
mark must leave it for 5.5 months or 5 and half moths to gain 5600 in interest .
<u>Step-by-step explanation:</u>
Here we have , mark invests 8000 in an account that pays 12% interest and 2000 in one that pays 8%. if he leaves the money in the accounts for the same length of time, We need to find how long must he leave it to gain 5600 in interest . Let's find out:
Let mark invests 8000 in an account that pays 12% interest and 2000 in one that pays 8% for time x months , So total interest gain is 5600 i.e.
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Therefore , mark must leave it for 5.5 months or 5 and half moths to gain 5600 in interest .
7a
TSA = 2lw<span> + 2</span>lh<span> + 2</span><span>wh
TSA = 140 + 70 + 100 = 310 ft^2
7b
310 x $4 =$1240
cost = </span>$1240
7c
V= wlh = <span>7×10×5 = </span><span>350 ft^3</span>