In order to verify the equation sin (θ +π/4) =-cosθ. What value would you need to know besides sin (π/4)? Group of answer choices

a cos (π/4)

b sin (2π/3)

c tan (2π/3)

d cos ((-π)/3)

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of