it looks like its answers two, four, and five.
tell me how you did !
Mark spend 1 hour 10 minutes in reading.
<h3>What is Unitary Method?</h3>
Unitary method is a process by which we find the value of a single unit from the value of multiple units and the value of multiple units from the value of a single unit.
Mark spent 1 hour 17 minutes less than Sheila
Sheila spent 55 minutes less than Pete.
Pete spent 3 hours reading.
Since, pete spent 3 hours. So, Sheila spent
= 3 hours or (180 minutes) - 55 minutes
= 2 hours 05 minutes.
Now, Mark spent = 2 hrs 05 minutes - 55 minutes
= 1 hour 10 minutes
Learn more about unitary method here:
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Step-by-step explanation:
Answer:
14.99 hours
Step-by-step explanation:
The formula for half-life is given as,
R/R' = 2ᵃ/ᵇ...................... Equation 1
Where R= Original mass of sodium-24, R' = mass of Sodium-24 after disintegration, a = Total time taken for sodium-24 to disintegrate, b = half-life of sodiun-24.
Given: R = 1 kg, R' = 0.0156 kg, a = 90 hours
Substitute into equation 1 and solve for b
1/(0.0156) = 2⁹⁰/ᵇ
Taking the log of both side
log[1/(0.0156)] = log(2⁹⁰/ᵇ)
log[1/(0.0156)] = 90/b(log2)
90/b = log[1/(0.0156)]/log2
90/b = 6.0023
b = 90/6.0023
b = 14.99 hours
b = 14.99 hours.
Hence the half-life of Sodium-24 is 14.99 hours
The height of the object is EQUAL to the height of the model. We can see this in advertising when for example cereal is being advertised and on the box is says "actual size" because the cereal is drawn to scale.
