Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: LG 60PC1D 60-Inch 720p Plasma HDTV
Product description: LG 60PC1D 60" Plasma HDTV
Product feature: 60" Plasma Integrated HDTV with Built-in ATSC/NTSC/QAM Tuner to receive Digital Broadcast Signals and Unscrambled Digital Cable, LG's Clear Filter Pro improves brightness and contrast reduces reflection for Truer Color Reproduction with 60,000 Hours, Extreme Contour Compensation (XCC) minimizes Contour Noise for natural color and Image Sticking Minimization Provides Protective Measure, LG's Exclusive XD engine uses six distinct processes to improve brightness, contrast, detail, and enhances color, 2 HDMI/HDCP inputs 2 HD Component Video inputs Digital Optical Audio Output RGB input and Side mount AV Inputs with S-Video and Remote Control
Product brand: LG
Target attributes: Refresh Rate
Answer: attribute: refresh rate
value: None
source: None