Preston has calculated that his drink coaster has an area of 78.5 square centimeters. What is the coaster’s radius? Use 3.14 for pi

The coaster’s radius is 5 cm

Step-by-step explanation:

Drink Coaster has a circular shape.

Area of a circle = π*r²

so, area of the drink coaster = π x (Radius of the drink coaster)²

Given that Area of the drink coaster is 78.5 cm²

∴ 78.5 cm² = π*r²

Also we are to use 3.14 for π

∴ 78.5 cm² = 3.14*r²

   r² = 78.5 cm² / 3.14

   r² = 25 cm²

   r = cm

   r = 5 cm

Hence, the coaster’s radius is 5 cm

answer set (b) 0.5, 3/4 80% is in order from least to greatest.  

step-by-step explanation:

in order to compare rational numbers to each other, it is much easier if they are in the same form.   typically, the best form in which to evaluate rational numbers is in decimals.   in order to convert a percent to a decimal, you would divide the given percentage by 100.   you can also accomplish the conversion by moving the decimal point over two places to the left.   for example, the decimal value of 80% is 80/100, or 0.8.   in order to convert a fraction to a decimal, you need to divide the numerator by the denominator.   for example, 3/4 is 0.75.   so, for choice (b) 0.5 3/4 (0.75), 80% (0.8) is the only choice in which the numbers are in order from least to greatest.