Hello, can someone please help me with these two questions? The material does not explain how to figure these out and I am struggling.

You are estimating the cost of optical sensors based on the radius of the sensors. You decide to calculate the coefficient of determination (R²) as part of determining the goodness of fit of an equation. Using the preliminary calculations below, calculate the R² and determine its meaning.

[Image Description:

Summation of (Y_i-Ybar)² = 150000, Summation of (Yhat-Ybar)² = 125000, Summation of (Y-Yhat)² = 25000]

a.83.33% of the variation in the cost is being explained by the radius.

b.83.33% of the variation in the radius is being explained by the cost.

c.16.67% of the variation in the cost is being explained by the radius.

d. 16.67% of the variation in the radius is being explained by the cost.

Given the following information, determine the equation for the unit formulation. (Round intermediate calculations to 4 decimal places)

[Table Description: Table listing Unit Number (X) and Unit Cost ($Y).

Unit 1 = $1200.00,

Unit 2 = $975.00,

Unit 3 =$863.48,

Unit 4=$792.19

a. Y = (1200)(X) ^-0.2065

b.Y = (1200)(X) ^-0.2996

c. Y = (1200)(X) ^0.8667

d. Y = (1200)(X) ^0.8125