Answer: The correct option is D: Is alloyed with carbon and chromium to make stainless steel.
Explanation: Because of its physical characteristics, iron is a material that tends to oxidize easily. With the chromium alloy stainless steel is created, which for its quality can be used in the manufacture of structural steels.
Hello :
v . w = <span>| | v | | × </span><span>| | w | | cos(</span><span>θ) ....(1)
v(2,0,1) w(0,1,-3)
</span>v . w = (2)(0)+(0)(1)+(1)(-3) = - 3
| | v | | = √((2)²+(0)²+(1)²) = <span>√5
</span>| | w | = √((0)²+(1)²+(-3)²) = √10
by (1) :
cos(θ) = (v . w ) / | | v | | × | | w | |
cos(θ) = = - 3/√50
θ =..... calculate by 2ind function ( calculator)
Answer:
C
Step-by-step explanation:
y-3=5(x-2) (rearrange this to be in slope- intercept from) (add 3 to both sides)
y = 5(x-2) + 3 (distribute parentheses)
y = x(5) - 2(5) + 3
y = 5x -10 + 3
y = 5x - 7
recall that for a line with gradient m, the gradient of the perpendicular line will be - (1/m)
hence in our case, our gradient of the original line is 5, hence the gradient of the perpendicular line is -1/5
From the choices, the only one that is consistent with this is C
i.e choice C:
5y + x = 25
5y = -x + 25
y = -(1/5) x + 5 ===> gradient of -1/5
Answer:
d.a cluster sampling
Step-by-step explanation:
This plan exemplifies Cluster sampling. It is a sampling method where populations are placed into different separate groups like here into freshman, sophomore, junior, and senior classes. A random sample of these groups is then selected as here thirty students selected from each group to represent a specific population.<u> It is usually used in that type of research when there is no possible way to find information about a population as a whole.</u>