we can use formula
where
fL is listener frequency
fs is siren frequency
va is the speed of sound in air
vs is police car speed
so, we have
now, we can change it into m/s
now, we can plug it
..............Answer
Bacteria begins to grow on the water's surface in a non-operational swimming pool on September 20. The bacteria grows and covers
the water's
surface in such a way that the area covered with bacteria doubles every day. If it continues to grow in this way, the water's surface will be
entirely covered with bacteria on September 28.
When will a quarter of the water's surface be covered?
O A.
The water's surface will be covered a quarter of the way on September 24.
B.
The water's surface will be covered a quarter of the way on September 26.
C.
The water's surface will be covered a quarter of the way on September 27.
OD. The water's surface will be covered a quarter of the way on September 25.
surface in such a way that the area covered with bacteria doubles every day. If it continues to grow in this way, the water's surface will be
entirely covered with bacteria on September 28.
When will a quarter of the water's surface be covered?
O A.
The water's surface will be covered a quarter of the way on September 24.
B.
The water's surface will be covered a quarter of the way on September 26.
C.
The water's surface will be covered a quarter of the way on September 27.
OD. The water's surface will be covered a quarter of the way on September 25.
2 answers:
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Answer:
14.04 miles per hour
Step-by-step explanation:
The problem is asking for Izumi's speed. The formula of speed is:
- s =
, where "s" means speed, "d" means distance and "t" means time.
The problem is also asking for the unit<u> miles per hou</u>r () so, this means that we have to know how many miles Izumi ran, given that the problem only mentioned<u> yards (110 yards).</u>
Let's convert 110 yards to miles, provided that he Izumi ran 1,760 yards in a mile.
- 110 yards ÷ 1760
= 0.0625 miles (this is the distance covered by Izumi in miles)
Let's go back again to the formula: s =
s = = 0.0039
Since, the we arrived at a miles per second unit, we have to convert it to miles per hour.
So, if a minute has 60 seconds, then an hour has 3,600 seconds.
Thus, 0.0039 × 3,600
= 14.04 miles per hour (the answer)