Answer:
Time = 80.91 seconds
Explanation:
Given the following data;
Velocity = 5.50 m/s.
Distance = 445 meters
To find the time;
Velocity can be defined as the rate of change in displacement (distance) with time. Velocity is a vector quantity and as such it has both magnitude and direction.
Mathematically, velocity is given by the equation;

Substituting into the formula, we have;
5.5 = 445/time
Time = 445/5.5
Time = 80.91 seconds
Explanation:
First we will convert the given mass from lb to kg as follows.
157 lb = 
= 71.215 kg
Now, mass of caffeine required for a person of that mass at the LD50 is as follows.

= 12818.7 mg
Convert the % of (w/w) into % (w/v) as follows.
0.65% (w/w) = 
= 
= 
Therefore, calculate the volume which contains the amount of caffeine as follows.
12818.7 mg = 12.8187 g = 
= 1972 ml
Thus, we can conclude that 1972 ml of the drink would be required to reach an LD50 of 180 mg/kg body mass if the person weighed 157 lb.
Answer:The central spot becomes Dark
Explanation: it become dark because as the wavelength reduces,the velocity in the detector decreases, this time by 90degrees
water, if this were to occur u would want to immediately wash it with well water.
Reason: Strong bases react with the oils in your skin to produce a soapy feeling layer. Rinse until well after that feeling is gone.
(a) The work done by the gas during the isothermal expansion is -25.6 J.
(b) The heat added to the gas during this process is 25.6 J.
<h3>
Net work done by the ideal gas against the external pressure</h3>
The net work done by the ideal gas in the isothermal expansion is calculated as follows;
W(net) = ΔP x ΔV
W(net) = ( 1 kPa - 5 kPa) x (8L - 1.6 L)
W(net) = -25.6 kPa.L
W(net) = -25.6 J
<h3>Head added to the gas</h3>
The heat added to the gas is calculated as follows;
W = -Q
-25.6 J = -Q
Q = 25.6 J
Learn more about Isothermal expansion here: brainly.com/question/17192821