Perform the operation indicated and collect like terms: 
Definitions:
Cross-Sectional Studies
Research designs in which subjects of different ages are studied at one point in time.
Developmental Trends
Describes the patterns and directions of growth, change, or progress in any developmental aspect over a period.
Positive Correlation
A relationship between two variables in which both variables move in the same direction.
Intelligence
The capacity for learning, understanding, and applying knowledge and skills, often measured through cognitive tests and assessments.
Q12: The current exchange rates show that US$1.00
Q18: Evaluate to six-figure accuracy: <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB4281/.jpg" alt="Evaluate
Q20: The Hampton District school board decided to
Q22: Nancy borrowed $8,000 from her grandfather to
Q25: The price of a box of chalk
Q50: In January of 2008, the federal government
Q56: Solve for the following pair of equations
Q97: An annuity providing a rate of return
Q118: What number is 25% less than 96?<br>A)
Q227: Stanford Marketing raised $2.1 million to launch