I need help and this is the 3rd time I am asking you can have extra points for the othe ones

steps below

Step-by-step explanation:

a,b in 2nd quadrant: sine is positive and cosine is negative

sin a = 3/4      cos a = -√7/4

cos b = -12/13    sin b = 5/12

sin(a+b) = sin a cos b + cos a sin b

             = 3/4*(-12/13) + (-√7/4)*(5/12)

             = - 9/13 - (5√7/48)

             = -0.9679

cos(a-b) = cos a cos b + sin a sin b   (can you try yourself?)

connie < felicia < stew

step-by-step explanation:

stew:

we need to find the slope

m = (y2-y1)/ (x2-x1)

    = (2650-795)/(10-3)

    = 1855/7

265 words per minute

connie:

we need to find the slope

m = (y2-y1)/ (x2-x1)

we have two points (0,0) and (4,800)

m = (800-0)/(4-0)

  m = 800/4

    200 words per minute

felicia:

260 words per minute

200< 260 < 265

connie < felicia < stew

if you need just tell me and i will come to the rescue.

step-by-step explanation: