Answer:
The focal length of the lens should be -51.5 cm (a concave lens).
Explanation:
The purpose of the lens is to make objects at 48.5 cm appear at the healthy near point. The healthy near point is 25.0 cm.
We use the lens formula

where <em>f</em> = focal length, <em>u</em> = object distance and <em>v</em> = image distance.
In this case, <em>u</em> = 48.5 cm and <em>v</em> = -25.0 cm.
<em>v</em> is negative because the image is virtual an not real. (Here, we are using the real-is-positive sign convention)


The negative sign indicates the lens is concave.
Explanation:
<h2>Global warming is the unusually rapid increase in Earth's average surface temperature over the past century primarily due to the greenhouse gases released as people burn fossil fuels.</h2>
Answer:
15 to 30 so anywhere in between there.
Answer:
New pressure (P2) = 22.92 Kpa (Approx)
Explanation:
Given:
Old pressure (P1) = 22 Kpa
Temperature (T1) = 287 K
Temperature (T2) = 299 K
Find:
New pressure (P2)
Computation:
P1 / T1 = P2 / T2
22 / 287 = P2 / 299
New pressure (P2) = 22.92 Kpa (Approx)
An object either remains at rest until acted upon