An observation study is where nothing changes and you record what is seen. An experimental study you have a control group and a testable group.
The answer would be: .C. The groups in an experiment are chosen at random, but not in an observational study.
A. h = 30Ft * 1.26cm/Ft = 37.8 cm. = Ht. of the model.
37.8cm * 1toothpick/6.3cm = 6 Toothpicks
B. 37.8cm/7.6 = 4.97 hope this helped.
The way to find the area of a triangle is A=

if the base is 3 feet longer then the height we can write it like this B=H+3
now we can add it to our area equation
20=

20=

40=

+3H
10

=

h=3.2ft
Step-by-step explanation:Step 1: Simplify both sides of the equation.
4−(2y−1)=2(5y+9)+y
4+−1(2y−1)=2(5y+9)+y(Distribute the Negative Sign)
4+−1(2y)+(−1)(−1)=2(5y+9)+y
4+−2y+1=2(5y+9)+y
4+−2y+1=(2)(5y)+(2)(9)+y(Distribute)
4+−2y+1=10y+18+y
(−2y)+(4+1)=(10y+y)+(18)(Combine Like Terms)
−2y+5=11y+18
−2y+5=11y+18
Step 2: Subtract 11y from both sides.
−2y+5−11y=11y+18−11y
−13y+5=18
Step 3: Subtract 5 from both sides.
−13y+5−5=18−5
−13y=13
Step 4: Divide both sides by -13.
−13y
−13
=
13
−13
y=−1
Answer: y =-1
Answer:

Step-by-step explanation:
