Saying no when poeple offer it to you
Answer:
Explanation:
Forehand groundstroke effectiveness is important for tennis success. Ball topspin angular velocity (TAV) and accuracy are important for fore hand groundstroke effectiveness, and have been extensively studied, previously; despite previous, quality studies, it was unclear whether certain racquet kinematics relate to ball TAV and shot accuracy during the forehand groundstroke. This study evaluated potential relationships between (1) ball TAV and (2) forehand accuracy, and five measures of racquet kinematics: racquet head impact angle (i.e., closed or open face), horizontal and vertical racquet head velocity before impact, racquet head trajectory (resultant velocity direction, relative to horizontal) before impact, and hitting zone length (quasi-linear displacement, immediately before and after impact). Thirteen collegiate-level tennis players hit forehand groundstrokes in a biomechanics laboratory, where racquet kinematics and ball TAV were measured, and on a tennis court, to assess accuracy. Correlational statistics were used to evaluate potential relationships between racquet kinematics, and ball TAV (mixed model) and forehand accuracy (between-subjects model; α = 0.05). We observed an average (1) racquet head impact angle, (2) racquet head trajectory before impact, relative to horizontal, (3) racquet head horizontal velocity before impact, (4) racquet head vertical velocity before impact, and (5) hitting zone length of 80.4 ± 3.6˚, 18.6 ± 4.3˚, 15.4 ± 1.4 m·s-1, 6.6 ± 2.2 m·s-1, and 79.8 ± 8.6 mm, respectively; and an average ball TAV of 969 ± 375 revolutions per minute. Only racquet head impact angle and racquet head vertical velocity, before impact, significantly correlated with ball TAV (p < 0.01). None of the observed racquet kinematics significantly correlated to the measures of forehand accuracy. These results confirmed mechanical logic and indicate that increased ball TAV is associated with a more closed racquet head impact angle (ranging from 70 to 85˚, relative to the ground) and increased racquet head vertical velocity before impact.
This kind of exposure is called caustic exposure.
Explanation:
A caustic exposure is an exposure to chemicals present in common household cleaning products like detergents, cleaning solutions, drain cleaners etc.
These contain caustic substances (strong concentration of acid or base) like sodium hydroxide, sulfuric acid etc. When exposed directly on to the skin, due to its stronger concentration, it may burn the skin causing redness, irritation, numbness, or blackening of the skin surface.
Most of the times, these marks go away after some weeks because they are superficial or first-degree burn where only the epidermal layer of the skin gets affected.
It increases the likelihood that key points will be included.
Start an activity that does not require extra equipment because the student is actually doing the work. You can conduct as much research as you want but that doesn't mean the student will actually do the activities.
