The difference is 180 is the correct answer for the problems
Answer:
18
Step-by-step explanation:
30*0.4=12
This means 40% of 30 is 12 and Ana has completed 12 problems.
30-12 = 18, so she still needs to do 18 problems.
B,13 students prefered math
If you reverse the first two letters
Na
Fe
Hg
Sn
They are actually symbols for elements
Na - Sodium
Fe - Iron
Hg - Mercury
Sn - Tin
Since Sn is a symbol for Tin and each pair of letters imply the starting letter of the element they are symbolizing, the answer is
1) T<span />
The height is represented by h = -16t² + 4t + 20 and There is only one solution, because the solutions indicate time and time cannot be negative.
<h3>How to solve vertical motion models?</h3>
We are given the vertical model of the diver's jump as;
h = -16t² + vt + s
where;
h is height
t is time
v is velocity
s is distance
A) We are given;
Distance; s = 20 ft
velocity; v = 4 ft/s
Thus;
h = -16t² + 4t + 20
B) The solution of the model is gotten from;
-16t² + 4t + 20 = 0
Solving this quadratic equation gives;
t = 1.25 seconds or -1 second
C) B. There is only one solution, because the solutions indicate time and time cannot be negative.
Read more about Vertical Motion Models at; brainly.com/question/27526920
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