Please provide a neat solution. You may use a calculator technique but explain the concepts or formula you will use. Thank you.

Items 89-100:

88. The third term of an arithmetic progression is - 7 and the eighth term is 23. Find the sum of the first 12 terms. A. 280 B. 221 C. 121 D. 168 80. Mrs. Smith is twice as old as her daughter Sam. Ten years ago. the sum of their ages was 46 years. How old is Sam? A 12 B. 15 C. 22 D. 19 80. The angle or inclination of ascend of a road having 8.25% grade is _ degrees. A. 4.72 B. 4.27 C. 5.12 D. 1.88 01. Find the volume generated by revolving about the y awis the area bounded by the curve y = (x squared) +4 and y = 2 ( x squared ) A 6 pi B. 18/3 pi C. 7 pi D. 8 pi 82. Find the number of ways in which 6 teachers can be assigned to 4 sections of an introductory psychology course if no teacher is assigned to more than one section. A. 60 B. 240 C. 120 D. 360 83. Justine's average in 5 subjects is 80. Disregarding the lowest grade his average is 90. What is Justine's lowest grade? A. 85 B. 86 C. 87 D. Be 04. A triangle is defined by the points (2,6). (-2,2) & (5,2). Find the area of the triangle. A. 28 B. 14 C. 12 D. 10 85. What is the number of the sides of the polygon if the sum of the angles is 1440 degrees? A 6 B. 8 C. 9 D. 10 08. The largest triangle that can be inscribed in semi-circle. A. Right Triangle C. Isosceles Triangle B. Scalene Triangle D. Equilateral Triangle 07. The plate number of a vehicle consists of 5 alphanumeric sequence is arranged such that the first 2 characters are alphabet and the remaining 3 are digits. How many arrangements are possible if the first character is a vowel and the repetitions are not allowed? A. 20 900 C. 8000 D. 20000 08. Joey gives 1/4 of his candies to Jake. Jake gives 1/5 of his candies to Jose. Jose receives 2 candies. How many candies does Joey has at first? A. 10 B. 20 C. 30 D. 40 82. In how many ways can a person choose 1 or more of 4 electrical appliances? A 12 B. 13 C. 14 D. 15 100. A square garden with a side of 20 m is to be illuminated by a bulb at the center. If the radius of the covered light is 10 m, what should be the area of un-shaded garden? A. 65 sq. meters C. 85 sq meters B. 75 sq. meters D. 95 sq meters