Answer:The highest possible efficiency of this heat engine is 11%
Explanation:
Saturated water temperature at P1, Pressure in Heat addition,
1.1 MPa=185°C +273= 458K
Saturated water temperature at P2, Pressure in Heat rejection,
0.3MPa=133.5°C+ 273=406.5K
The highest possible efficiency of any heat engine is the Carnot efficiency given as
Carnot efficiency, ηmax = 1- (T2/ T1)
1- (406.5K/458K)
1-0.88755=0.112
=11%
1) Focal length
We can find the focal length of the mirror by using the mirror equation:

(1)
where
f is the focal length

is the distance of the object from the mirror

is the distance of the image from the mirror
In this case,

, while

(the distance of the image should be taken as negative, because the image is to the right (behind) of the mirror, so it is virtual). If we use these data inside (1), we find the focal length of the mirror:

from which we find

2) The mirror is convex: in fact, for the sign convention, a concave mirror has positive focal length while a convex mirror has negative focal length. In this case, the focal length is negative, so the mirror is convex.
3) The image is virtual, because it is behind the mirror and in fact we have taken its distance from the mirror as negative.
4) The radius of curvature of a mirror is twice its focal length, so for the mirror in our problem the radius of curvature is:
Answer:
The answer is 631.157
Explanation:
The question requested that the answer to the subtraction of 26.543 from 657.70 must be written using significant figures.
Here are a few tips about how to Identify significant figures.
1) It should be noted that <u>the number "0" is what is usually (but not always) affected</u> while trying to identify significant figures. Hence, <u>all other numbers/digits are always significant</u>. For example, 26.543 has five significant figures.
2) The zeros found between these "other numbers/digits" are also significant. For example, 2202 has four significant figures.
3) In the case of a decimal, the tailing zeros or the final zero is also significant. 657.70 and 657.07 have five significant figures.
Now, back to the question
657.70 - 26.543 = 631.157.
Our final answer does not have a zero, hence all the digits (six) are significant.