Akitchen was remodeled and granite counter tops were installed. a rectangular island in the kitchen now has a granite top measuring 5 ft. by 8 ft. by 1.2 inches. the density of granite is 2.7 g/cm. how much does the granite top on the island weigh, in pounds? (round to nearest tenth of a pound.)

674.2 lb

Step-by-step explanation:

First we transform all the units into cm

5 ft = 152,4 cm

8 ft = 243.84 cm

1.2 in = 3.048 cm

The volume of the granite rectangular top can be found by multiplying its three sizes

Volume = (152,4 cm)*243.84 cm * 3.048 cm

Volume  = 113267.3864  cm^3

We know that

Density  = mass/ volume

Mass = Density * Volume

Mass = 2.7 g/cm^3  * ( 113267.3864  cm^3)

Mass = 305821.9432  g  = 305.822 Kg

We transform grams to pounds

305821.9432  g  = 674.22197 lb

= 674.2 lb

it is a. 4.2 because 7.6-3.4 gets the remaining length of 4.2. i might be wrong but i am pretty sure this is the answer.