Help will give brainliest

72

Step-by-step explanation:

Step 1: Figure out percentages of what he owns

360(0.4) = 144 models he made

360 - 144 = 216 models he bought.=

Step 2: Figure out percentages of what he donated

144(0.25) = 36 models he donated (he made)

216(0.5) = 108 models he donated (he bought)

Step 3: Find the difference

108 - 36 = 72

And we have our answer!

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places

where is the diagram? shown below where? ?

step-by-step explanation: