Alittle would be !

braxton is testing 2 different types of motor oil in his truck to determine which one lasts longer between oil changes. he purchases brand a and brand b from the auto parts store. he adds brand a to his truck and brand b to his sister's car. he then compares the color of the oil at the end of the week from both vehicles and determines that brand b goes longer between oil changes because it is lighter in color than that of brand a when he examines it. why is braxton's conclusion not valid?

a. he added brand b to his sister's car, not the truck.
b. he did not determine the starting color of the oil.
c. he purchased 2 different types of oil.
d. he added brand a to his sister's car, not the truck.

The correct option is A.

Step-by-step explanation:

Braxton is testing 2 different types of motor oil in his truck to determine which one will last longer.

Now, he adds Brand A to the truck and Brand B to his sister's car.

Now, as Braxton wants to test the motor oil in his truck so there is no need of adding the motor oil to his sister's car as by doing so he cannot result in to a meaningful conclusion.

So, Braxton need to add both the motor oil into his truck one by one.

Hence, The conclusion of Braxton is not valid because he added Brand B to his sister's car, not the truck.

Therefore, The correct option is A.

2.2°  

step-by-step explanation:

let θ = the angle of elevation.

tanθ =77/2020

tanθ = 0.038 12

      θ = tan⁻¹0.038 12

      θ = 2.2°