1) i .j = ? (they are unit vectors of each axis) 2) What is cose, 0 is the angle between (2i +j) and (2i -j)? 3 ) ( 21 + 1 ) . ( 21 - 1 ) = ? 4) The angle betweena and b is 30. So a . b=? ( a) V3/2 ( b) v3/2 1allbl ( C ) 1/2 ( d) 1/2 1allbl 5) a is projected onto the line wherebis, to become a'. What is la'll bl ?6) A person is using a horizontal (parallel to the horizon] force of 100N to push a box up a 50m slope, which has a 300 incline. How much work will be done to the box? 7) A sleigh is being pulled with a force of SON (which has an angle, see picture), over 30m. The sleigh never left the ground. How much work is done to the sleigh? (a) 1500 J (b) 1500 sin4001 (c) 1500 c0s40J (d) 1500 tan40J