Kevin and Amy are working on an experiment in the science lab. They start with 2.3 grams of oil and add water
to get exactly 4.21 grams of solution. To find the amount
of water added, they subtract the weight of the oil from the
weight of the solution. Kevin calculates the difference to
be 3.98 grams; Amy calculates it to be 1.91 grams.
Who is correct, and why?
4.21
4.21
Kevin -2.3 Amy -2.30
3.98
1.91
A. Amy is correct. Kevin did not regroup properly

7! = 7×6×5×4×3×2

3! = 3× 2

as 7! is multiple of 3! because 7! contains 3! that is 3× 2 as factor

so 7! /(3! ) = 7× 6× 5× 4

= 42 × 20

= 840

its b) 840✌✌✌

dhruv⭐

the equation cos(35) =a/25 can be used to find the length of bc what is the length of bc? round to the nearest tenth

step-by-step explanation:

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!

answer: 1inch=7days  

12inch=12*7=84days

step-by-step explanation: