Answer:
b) directional
Explanation:
The prediction that alcohol slows reaction time is Directional . This is because for alcohol to be known as one which slows reaction time means there have been various hypothesis conducted which supports this.
In this case, formulation of a null hypothesis is usually necessary which means that alcohol does not slow reaction time and another alternative hypothesis that suggests that alcohol slows reaction time.
Answer:

Explanation:
First of all, we need to find the pressure exerted on the sphere, which is given by:

where
is the atmospheric pressure
is the water density
is the gravitational acceleration
is the depth
Substituting,

The radius of the sphere is r = d/2= 1.1 m/2= 0.55 m
So the total area of the sphere is

And so, the inward force exerted on it is

Answer:
false, because a phase change occurs physical changes when matter changes its energy state.
Answer:
Explanation:
From the given information:
Since both stars are in the same cluster, the magnitude and luminosity relationship can be calculated as:

Given that;
m_1 = 1 and
m_2 = 4
Therefore,


Making
the subject of the formula:

=15.84
≅ 16
Hence, we can conclude that star X is more luminous by a factor of 16
Considering conservation of mechanical energy we have:
K+U (start)= K+U (end)
Where:
K=kinetic energy=

U=potential energy=

So:
0.05*0.95*9.81+0 (start) = 0+K (end)
K (end)=0.5 Joules