A circle has an area of 81π in2. Which of the following is the circumference of the circle in terms of pi ( π)?

A dependent variable is one that changes when another variable changes. In this case, the cost of the phone will change depending on the change inbrand name, size of the RAM, and size of the battery. Thus, cost of a phone is a dependent variable.

9/20 is the same as 9 divided by 20, which is evaluated 9÷20. The value becomes 0.45.

Thus, 9/20 is equal to 0.45.

The slope represents the ratio of rise to run. Let p be the minimum length of the ramp, we can set a ratio equation as follows. Then,

The minimum length of the ramp needed is 18 feet to access to a door that is 1.5 feet above the sidewalk.

We are asked to make z the subject of the formula.

First, we subtract y/x from both sides of the equation

Thus, the formula for finding the value of z is  .

we are tasked to find the number of cups of flour that will be used to make 90 cookies.

This is a proportion equation, and letting x be the number of cups of flour we set the equation as follows:

Solve the value of x by cross-products

Next, we convert the mixed fraction into improper fraction in order to carry out multiplication

The baker needs 15.75 cups of flour to make 120 cookies.  15.75 in mixed fraction is  

We are asked to convert kg to pounds using the given relation. If we let x to represent the lb we are asked to find, we set the proportion equation with kg on numerator and lb on the denominator as follows.

The equivalent value of 55kg is 121 lb.

An independent variable is a variable that is manipulated or changed in the experiment. From the given equation, x is variable that is changed to obtain the desired outcome, F(x). Therefore, x is an independent variable.

we are asked to find the percent change in weight gain of a person.

First, we need to find the change in weight gained over the 4 months

Change in weight= 186-176=10 lb

The percent change is expressed as change in weight over original weight *100. Then

The percent change in weight is 6% to the nearest whole number.

By inspection, we find the corresponding values of the given denominations in the following manner.

The SI units of measuring length is meter. However, a meter can be a large unit or small quantity depending what is being measured. Therefore, derived units of meters are used to measure the length of an object. In our case, centimeters is the appropriate unit to measure the width of the window.