A woman’s menstrual cycle usually lasts about 28 days *TRUE*
Answer:

Explanation:
Hello,
In this case, it is convenient to compute the car's mileage in km/L as follows:

In such a way, since the distance is measured to be 250 km, the volume requirement is:

Regards.
The number of years required for 1/4 cobalt-60 to remain after decay is calculated as follows
after one half life 1/2 of the original mass isotope remains
after another half life 1/4 mass of original mass remains
therefore if one half life is 5.3 years then the years required
= 2 x 5.3years = 10.6 years
Answer:
0.00471 grams H₂O
Explanation:
To determine the mass, you need to use the following equation:
Q = mcΔT
In this equation,
-----> Q = energy/heat (J)
-----> m = mass (g)
-----> c = specific heat capacity (J/g°C)
-----> ΔT = temperature change (°C)
The specific heat capacity of water is 4182 J/g°C. You can plug the given values into the equation and simplify to isolate "c".
Q = 0.709 J c = 4182 J/g°C
m = ? g ΔT = 0.036 °C
Q = mcΔT <----- Equation
0.709 J = m(4182 J/g°C)(0.036 °C) <----- Insert values
0.709 J = m(150.552) <----- Multiply 4182 and 0.036
0.00471 = m <----- Divide both sides by 150.552
Answer:
The answer is: <u>Al2O3</u>
Explanation:
The data they give us is:
To find the empirical formula without knowing the grams of the compound, we find it per mole:
- 0.545 g Al * 1 mol Al / 27 g Al = 0.02 mol Al
- 0.485 g O * 1 mol O / 16 g O = 0.03 mol O
Then we must divide the results obtained by the lowest result, which in this case is 0.02:
- 0.02 mol Al / 0.02 = 1 Al
- 0.03 mol O / 0.02 = 1.5 O
Since both numbers have to give an integer, multiply by 2 until both remain integers:
Now the answer is given correctly: