Select the Missing number?

In a certain code language, '+' represents 'x', '-' represents '+', 'x' represents '÷' and '÷' represents '-'. What is the answer to the following question?
550 x 22 - 24 + 3 = ?

From the given words, select the word which cannot be formed using the letters of the given word.
FAMISHED

The weights of 4 boxes are 20, 30, 50 and 70 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxes and in a combination a box can be used only once?

A series is given, with one number missing. Choose the correct alternative from the given ones that will complete the series.
-4, ? , 1, 3.5, 6, 8.5

A series is given, with one term missing. Choose the correct alternative from the given ones that will complete the series.
K, J, L, I, M, ?

A series is given, with one word missing. Choose the correct alternative from the given ones that will complete the series.
nephew, anther, tenses, prunes, preens, ?

A passage is given with 5 questions following it. Read the passage carefully and choose the best answer to each question out of the four alternatives.

Due to poor rainfall over the past few months, the vadu mangai season is expected to be short this year. There are two distinct varieties available in the vicinity of Coimbatore. The closest to Coimbatore, and the one that appears in the markets first, is the Thadagam variety. The second and more popular variety is the one from the Thirumoorthy Hills, near Udumalpet. Representatives from commercial pickle brands whisk these mangais away in big lots directly from the wholesalers. Only a small portion of the year's harvest trickles down to the local markets. Small vendors bring sacks full of these tiny tender mangoes to one particular street corner in Ram Nagar during the season. The corner of Rajaji Road and Sathyamurthy Road plays host to these vendors from as early as 7.00 am every day. Depending on the quantity they have, the mangais are available until around 11.00 am. If the vendors have a good day and their produce is sold quickly, they pack up and leave even as early as 9.00 am.

Which of the following best describes the vadu mangai mangoes?