Answer:
2,38kg
Explanation:
Mass in function of time can be found by the formula:
, where
is the initial mass, t is the time and k is a constant.
Given that a sample decay 1% per day, that means that after first day you have 99% of mass.
, but
, so we have
, then 
Now using k found we must to find
.

The gap between the two flasks is partially evacuated of air creating a near vacuum which significantly reduces heat transfer by conduction or convection
Answer: (2) Use the Momentum Principle.
Explanation:
In fact, it is called the <u>Conservation of linear momentum principle,</u> which establishes the initial momentum
of the asteroids before the collision must be equal to the final momentum
after the collision, no matter if the collision was elastic or inelastic (in which the kinetic energy is not conserved).
In this sense, the linear momentum
of a body is defined as:

Where
is the mass and
the velocity.
Therefore, the useful approach in this situation is<u> option (2)</u>.
The minimum average speed it must have in the second half of the event in order to qualify is 414.7 km/h.
<h3>
What is average speed?</h3>
The average speed of an object is the ratio of total distance traveled by the object to the total time of motion of the object.
<h3>Total time taken by the car during the entire race</h3>
time = distance/average speed
time = (1.41 km) / (278 km/h)
time = 0.0051 hr
The car travels the first half of the race, d (¹/₂ x 1410 m) at 210 km/h;
d = 705 m = 0.705 km
t1 = 0.705/210
t1 = 0.0034 hr
<h3>time for the second half</h3>
t2 = 0.0051 - 0.0034 hr
t2 = 0.0017 hr
<h3>minimum average speed of the second half</h3>
v = d/t
v = 0.705 km / 0.0017 hr
v = 414.7 km/hr
Thus, the minimum average speed it must have in the second half of the event in order to qualify is 414.7 km/h.
Learn more about average speed here: brainly.com/question/4931057
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