The acceleration of a Maserati is proportional to the difference between 250 km/h and the velocity of this sports car. a) Write the differential equation governing the velocity. Use k for the proportionalty constant (assume k>0 ).

a) The differential equation for the velocity is given by

(dv/dt) = k(250 - v)

b) v(t) = 250 - e⁽⁵•⁵² ⁻ ᵏᵗ⁾

With units of km/h

Explanation:

Acceleration, a ∝ (250 - v)

But acceleration is widely given as dv/dt

(dv/dt) ∝ (250 - v)

(dv/dt) = k(250 - v)

where k = constant of proportionality

(dv/dt) = k(250 - v)

b) (dv/dt) = k(250 - v)

dv/(250 - v) = k dt

∫ dv/(250 - v) = ∫ k dt

- In (250 - v) = kt + c (where c is the constant of integration)

v(0) = 0; meaning, at t = 0, v = 0

- In 250 = 0 + C

c = - In 250 = - 5.52

- In (250 - v) = kt - 5.52

In (250 - v) = 5.52 - kt

250 - v = e⁽⁵•⁵² ⁻ ᵏᵗ⁾

v = 250 - e⁽⁵•⁵² ⁻ ᵏᵗ⁾

With units of km/h

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz

there is no correct list among the choices you've provided.

the list might look something like this:

-- baby human

-- piccolo

-- flute

-- soprano singer

-- trumpet

-- tenor singer

-- trombone

-- baritone singer

-- baritone horn

-- bass singer

-- tuba

since i had to make up the list myself, i made it easy on myself, and i didn't try to shuffle the string instruments and woodwinds into it too.